Conventionally, there have been proposed various types of seatbelt retractors which remove the slack of webbing in case of an emergency, such as vehicle collision or the like.
For instance, a spool for retracting the webbing has a locking base which is integrally provided therewith at one end thereof. In case of a vehicle collision, a pretensioner is activated, whereby the spool and the locking base rotate together at high speed in a webbing retracting direction. Subsequently, a stop member provided in the locking base is moved in a counter-clockwise direction relative to the locking base, while being guided in a guide groove to reach an active position. In this active position, the stop member comes in contact with the bottom of the guide groove. The stop member is released from latching claw of a quick-lock pawl and the quick-lock pawl is rotated clockwise by an urging force of a spring. As a result, the quick-lock pawl is engaged with internal teeth formed in a frame. Accordingly, a seatbelt retractor has been designed wherein the locking base and the spool are locked, preventing rotation thereof in a webbing-pull-out direction (for instance, refer to Japanese Laid-open Patent Publication No. 2006-327556).